EP1702677B1 - Vessel and device for generating electric fields in independent reaction spaces - Google Patents

Abstract

Container (A) comprises reaction spaces (RS), each of which contains at least one electrode pair for generating an electrical field in RS when a voltage is applied. At least two first electrodes in different RS are electrically connected and at least one second electrode of one RS is electrically connected, separately. Independent claims are also included for the following: (1) method for preparing (A); and (2) device (B) for electrically contacting at least one (A).

Description

The invention relates to a method for electrically contacting at least one container provided with electrodes, in which the electrodes of the container are contacted by contact elements, wherein the container is first placed on a table and then the table with the container and / or the contact elements are moved vertically until the electrical contact between the contact elements and the electrodes is established. The invention further relates to a device for electrically contacting at least one container provided with electrodes, with at least one table for placing the container and arranged on a device contact elements for contacting the electrodes of the container, wherein the table and / or the device for producing an electrical Contact between the contact elements and the electrodes is vertically movable / are.

Containers with multiple reaction chambers of the type mentioned are known and are used mainly in biochemical and pharmaceutical applications when a variety of reaction mixtures must be tested simultaneously. Particular applications include, for example, electroporation, electrofusion and electrostimulation of living cells, as well as all applications in which the reaction mixture must be exposed to an electric field. In this case, the aim is to provide as large a number of reaction spaces as possible, for example 96 or 384, in particular for HT analyzes (HT = high throughput), since a large number of samples should be tested in as short a time as possible. Such containers are generally referred to as multi-well plates, microtiter plates or multi-wells.

The known containers usually consist of a plurality of reaction spaces, each having two electrodes which are in contact with the reaction mixture, for example a cell suspension, in the reaction space. The two electrodes of a reaction space generate an electrical field when an electrical voltage is applied in the interior of the reaction space, wherein they have different polarities, for example, with direct current. The electrodes of the same polarity, d. H. For example, all cathodes and / or all anodes, different reaction spaces are either integrally formed or electrically coupled together so that they can be connected via a common electrical contact with the voltage source. Although such arrangements have the advantage that they have a relatively simple structure, the disadvantage here is that the electrical parameters for all reaction chambers are the same and thus an individual control of the individual reaction chambers is not possible.

From the US 2002/0028480 A1 For example, devices for electrical stimulation of living cells are known. In one embodiment, strip-shaped electrodes are applied in pairs to the bottom of a multi-well plate. The strip-shaped electrodes protrude into each of the individual reaction spaces of the plates and are thus in electrical contact with the reaction mixtures. The strip-shaped electrodes each have a contact surface at one of their free ends, to which a voltage generator can be connected. A pair of electrodes is in each case assigned to a number of reaction spaces. In a particular embodiment, the one electrodes, for example all the anodes, are short-circuited, while the respective other electrodes, for example the cathodes, are individually connected to one row. In any case, only whole rows of reaction spaces can be controlled in these known arrangements, ie the electrical parameters can consequently be adjusted individually only for individual groups of reaction spaces and not for each individual reaction space.

From the DE 199 17 571 A1 Furthermore, an electrode grid for electroporation reaction approaches is known, which consists of a planar arrangement of electrical conductors on the surface of an electrical insulator. The tracks face each other in ramifications and each include individual reaction zones for receiving the electroporation reaction approaches. The opposing tracks form upon application of an electrical voltage electrodes, wherein the individual tracks converge in each case in a main branch, which is connected to the voltage generator. Consequently, no different adjustment of the electrical parameters is possible with this known arrangement, so that all reaction zones have the same electrical conditions.

The WO 03/057819 A1 also describes, inter alia, multiwell plates in which electrodes of different reaction spaces are electrically connected to each other at least in pairs, so that here too the electrical parameters can be adjusted individually only for individual groups of reaction spaces and not for each individual reaction space.

From the US-A-5,964,726 For example, a method and device for introducing molecules into vesicles or cells is known, the device having a perforated plate through whose openings needle-shaped electrodes are guided. The electrodes have heads that can be brought into contact with an electrically conductive plate, which in turn is connected to a power supply. For passing electrical current through the vesicles or cells, the orifice plate is moved downwardly toward a petri dish containing the vesicles or cells until the electrodes contact the bottom of the petri dish. Since the electrodes are freely movable in the openings of the perforated plate, the electrodes then move upwards relative to the perforated plate in the direction of the conductive plate arranged parallel to the perforated plate until the electrical contact is established.

From the DE 199 28 410 A1 Furthermore, a device for electrically contacting a microchip provided with electrodes is known. The microchip has recesses for receiving substances or reagents. The device has a mounting plate for mounting the microchip and a structural unit with contact elements for contacting the electrodes of the microchip, wherein the structural unit for making an electrical contact between the contact elements and the electrodes is vertically movable.

It is an object of the invention to provide a method and a device for safe and reliable electrical contacting of the known container.

The object is achieved by a method for electrical contacting of the type mentioned, in which the contact elements for contacting the electrodes are passed from the bottom through at least one opening in the table.

In one embodiment of the method according to the invention, it is provided that the contact elements are arranged on a device, preferably a plate, and the device is moved vertically, in particular by means of a motor.

In a further embodiment of the method according to the invention it is provided that the table is moved for placing the container by means of a motor.

In a further embodiment of the method according to the invention it is provided that an interior space is provided in which the contact elements are arranged.

In a further embodiment of the method according to the invention it is provided that a housing opening is provided through which the container and / or the table is inserted into a housing.

In a further embodiment of the method according to the invention, it is provided that a voltage pulse for generating electric fields in the container is not triggered until the container is inside the housing.

The object is further achieved by a device for electrical contacting of the type mentioned, in which the table has at least one opening through which the contact elements for contacting the electrodes are guided from the bottom.

In an advantageous embodiment of the invention, the device is a plate on which the contact elements are arranged. In this case, the device can additionally be moved horizontally, in particular by means of a motor, be mobile.

Preferably, the table for mounting the container is also horizontally movable, in particular by means of a motor mobile. The table may be a perforated plate, wherein preferably the number of holes corresponds to the number of contact elements. The holes serve to pass the contact elements for electrical contacting of the electrodes.

It can also be provided an interior in which the contact elements are arranged. In this way, the electrical contacts in the interior of the device are arranged so that the safety of the persons operating can be ensured.

It is advantageous in this embodiment that a housing opening is provided, through which the container and / or the table can be inserted into the interior / is, which further increases the safety of the device.

The device according to the invention may, in an advantageous embodiment, have at least one electrical storage device or be connectable to at least one electrical storage device, wherein the storage device is preferably a capacitor. In this case, several memory devices can be connected in parallel or in series.

Furthermore, at least one switching element can be arranged between the storage device and the electrodes of the container and / or an electrical switching element can be assigned to each reaction space and / or each group of coupled electrodes, wherein the switching element is preferably a relay. By driving the switching elements while the individual electrodes or reaction chambers can be switched specifically and safely.

In a particularly preferred embodiment of the invention it is provided that the switching elements are mounted directly on the contact elements, preferably below the device on which the contact elements are arranged. This particularly advantageous arrangement allows a very compact design of the device according to the invention.

Figur 1

zeigt schematisch verschiedene Ansichten einer Ausführungsform eines erfindungsgemäßen Behältnisses zur Durchführung des erfindungsgemäßen Verfahrens,

1. a) perspektivische Ansicht,
2. b) Draufsicht von oben,
3. c) Draufsicht von unten;

Figur 2

zeigt Draufsichten auf besondere Ausführungsformen erfindungsgemäßer Behältnisse, die als Streifen in einen hierfür vorgesehenen Rahmen einsetzbar sind,

1. a) teilweise bestückter Rahmen;
2. b) vollständig bestückter Rahmen;

Figur 3

zeigt eine perspektivische Ansicht einer Ausführungsform des erfindungsgemäßen Behältnisses mit 96 Reaktionsräumen,

1. a) gesamte Mikrotiterplatte,
2. b) gesonderte Darstellung eines Reaktionsraumes;

Figur 4

zeigt schematisch eine Draufsicht auf die Unterseite des erfindungsgemäßen Behältnisses gemäß Figur 3;

Figur 5

zeigt eine schematische Darstellung der Anordnung von Kontaktelementen einer erfindungsgemäßen Vorrichtung;

Figur 6

zeigt eine schematische Darstellung einer weiteren Ausführungsform der Anordnung von Kontaktelementen einer erfindungsgemäßen Vorrichtung;

Figur 7

zeigt eine perspektivische schematische Darstellung einer erfindungsgemäßen Vorrichtung zur Kontaktierung eines erfindungsgemäßen Behältnisses;

Figur 8

zeigt Schaltbilder einer Anordnung zur Durchführung des erfindungsgemäßen Verfahrens,

1. a) Ausführungsform mit gemeinsamer Kathode,
2. b) Ausführungsform für eine Anordnung der Kontaktelemente, gemäß Figur 5;

Figur 9

zeigt ein Flussdiagramm, das die einzelnen Schritte einer Ausführungsform des der Erfindung zugrunde liegenden Verfahrens darstellt.

The invention is explained in more detail below with reference to the figures by way of example.

FIG. 1

shows schematically various views of an embodiment of a container according to the invention for carrying out the method according to the invention,

1. a) perspective view,
2. b) top view from above,
3. c) top view from below;

FIG. 2

shows top views of particular embodiments of containers according to the invention, which can be used as strips in a frame provided for this purpose,

1. a) partially assembled frame;
2. b) fully assembled frame;

FIG. 3

shows a perspective view of an embodiment of the container according to the invention with 96 reaction spaces,

1. a) entire microtiter plate,
2. b) separate representation of a reaction space;

FIG. 4

schematically shows a plan view of the underside of the container according to the invention according to Figure 3;

FIG. 5

shows a schematic representation of the arrangement of contact elements of a device according to the invention;

FIG. 6

shows a schematic representation of another embodiment of the arrangement of contact elements of a device according to the invention;

FIG. 7

shows a perspective schematic representation of a device according to the invention for contacting a container according to the invention;

FIG. 8

shows circuit diagrams of an arrangement for carrying out the method according to the invention,

1. a) common cathode embodiment,
2. b) embodiment for an arrangement of the contact elements, according to Figure 5;

FIG. 9

shows a flowchart illustrating the individual steps of an embodiment of the method on which the invention is based.

FIG. 1 shows a particularly advantageous embodiment of a container 1 according to the invention in various views. The container 1 is shown in perspective view a), in a plan view from above b) and a top view from below c). The container 1 according to the invention has 16 reaction spaces 2, which are each formed from a wall region 3. Each reaction space 2 comprises a pair of electrodes which consists of a first electrode 4 and a second electrode 5. While the wall portion 3 is made of a non-conductive material such as glass or plastic, the electrodes 4, 5 are made of a conductive material. The electrodes 4, 5 may for example consist of a metal, ie aluminum, copper, silver or gold. However, preference is given to electrodes which consist of a polymer which is doped with an electrically conductive substance. The doping may consist, for example, of carbon fibers, graphite, carbon black and / or carbon nanotubes and be present in the polymer in a concentration of 40-80% by weight. Such conductive polymers have the advantage that they can be produced simply and inexpensively by injection molding and, moreover, in contrast to metal electrodes, do not release any cytotoxic metal ions. The concentration of the doping in the polymer should advantageously be chosen so that the electrodes on the one hand have sufficient conductivity, but on the other hand, the sprayability is maintained. These properties are guaranteed within the concentration range of 40-80% by weight.

In each reaction space 2, the first electrode 4 and the second electrode 5 include a gap 6 which serves to receive a cell suspension in which, in addition to the living cells, biologically active molecules, for example nucleic acids, are dissolved. When an electrical voltage is applied to the pair of electrodes, an electric current flows through the cell suspension in the gap 6 and causes the biologically active molecules to be introduced into the living cells. This process is well known as electroporation. The two electrodes 4, 5 have opposite polarities when applying an electrical voltage, d. H. one electrode 4, 5 has a negative potential and thus serves as a cathode, while the other electrode 4, 5 has a positive potential and serves as an anode. Depending on the direction of the current flow, the first electrode 4 and the second electrode 5 can thus each serve either as a cathode or as an anode, the respective polarity being of no significance for the present invention. For example, with DC, the opposite polarities are fixed while they oscillate back and forth with alternating current, creating an alternating field.

To establish the electrical contact, each electrode 4, 5 contact surfaces 7 are assigned. For example, a memory device, preferably a capacitor, can be connected to the contact surfaces 7, by means of which the electric field within the gap 6 is generated by its targeted discharge. In the container 1 described in FIG. 1, the contact surfaces 7 are arranged on the underside 12 of the electrodes 4, 5, which becomes clear from the view c). In the present exemplary embodiment, the electrodes 4, 5 consist of a polymer doped with conductive material. The contact surfaces 7 are made of a contact material, which is very dense, preferably applied to the conductive polymer under the action of pressure and heat, ie, for example by hot stamping. The Contact material has a lower resistivity (23 ° C) or entrance or interface resistance than the conductive material of which the electrodes 4, 5 consist. In the present exemplary embodiment, the contact surfaces 7 consist of a copper foil which has been applied to the electrodes 4, 5 by means of hot embossing. As is clear from view c), the first electrodes 4, ie, for example, the part of the electrodes of the container 1, which has a same name when applying an electrical voltage, for. B. in DC all cathodes, a common contact surface 8. The contact surface 8 consists of a continuous strip which extends over all first electrodes 4 and completely covers them. In this way, all first electrodes 4 of the container 1 are electrically conductively coupled. This has the advantage that the container 1 according to the invention is simple and inexpensive to produce and the electrical contacting of the gleichpoligen electrodes can be done via a single electrical connection, which significantly reduces the overall equipment complexity. The respective second electrode 5 of a reaction space 2 has a contact surface 9 assigned only to it. Via the individual contact surfaces 9, therefore, the second electrodes 5 of each reaction space 2 are separately electrically connectable. In this way, the generation of electric fields in each reaction space 2 can be switched separately. The separate circuit of each reaction space 2 has the advantage that the electrical parameters for each reaction space 2 can be set individually, so that the individual located in the reaction chambers 2 cell suspensions or reaction mixtures can be exposed to different conditions.

In the present embodiment, the 16 reaction spaces 2 are arranged in two rows 10, 11 to eight reaction spaces 2. By means of this row-shaped arrangement, the first electrodes 4 of the reaction spaces 2 arranged on the same side of a row 10, 11 and the respectively oppositely disposed first electrodes 4 of the adjacent rows 10, 11 can be electrically conductively coupled. By this arrangement of the reaction chambers 2, the production of the container 1 according to the invention further simplified saves material and beyond facilitates the electrical contact. The fact that in the present embodiment, the contact surfaces 7, 8, 9 are arranged on the underside 12 of the electrodes 4, 5 in the bottom portion 13 of the container 1, the electrical contact can be made from below, which further simplifies the apparatus, especially if containers with very many reaction spaces, for example 96 and more, should find application. In addition, the fact that both electrodes 4, 5 can be contacted from below avoids the use of an electrode immersed in the cell suspension from above, which has a positive effect on the homogeneity of the electric field within the gap 6.

FIG. 2 shows in plan view a particular embodiment of containers 15 according to the invention, which in principle correspond to the containers 1 according to FIG. The containers 15 are also formed strip-shaped and have at least one head-side free end on a special fastening device 16, which serves to fasten in a frame 17. As shown in view a), the individual containers 15, each consisting of 16 reaction chambers, can be inserted individually into the frame 17 and removed again. In this way, the frame 17 can be reused even if the individual containers 15 must be discarded. This material can be saved and beyond the environmental impact of the product can be improved. The illustrated system may also be flexibly equipped with a different number of reaction spaces depending on the size of the frame 17. View b) shows a fully populated frame 17, which is equipped with six containers 15. In this way a total of 96 reaction spaces can be used, which corresponds to a standard microtiter plate.

FIG. 3 shows a further embodiment of a container 20 according to the invention, which in principle corresponds to the container 1 according to FIG. In contrast to the container 1 described above, however, the container 20 has a total of 96 reaction chambers 21, which in eight rows of eight Reaction chambers 21 are arranged. A single reaction space 21 is shown enlarged in perspective view b) enlarged. The reaction chamber 21 consists of a wall region 22 made of a non-conductive polymer which is cylindrical. The reaction space 21 also has a pair of electrodes consisting of a first electrode 23 and a second electrode 24. The two electrodes 23, 24 include a gap 25, which serves to receive the cell suspension or the reaction mixture. The wall portion 22 of the reaction space 21 is open to fill the gap 25 upwards, wherein the inner surface 26 tapers from the opening 27 in the direction of the gap 25 inwardly. Through this funnel-shaped configuration of the opening 27, the filling of the reaction space 21 is facilitated, since this forms a guide for pipette tips. The gap 25 narrows moreover by lateral inflow of the side wall 28 downwards, so that it ends practically tip-shaped in the bottom region. This ensures that even lower volumes, for example less than 100 μl, are reliably absorbed in the gap 25 between the electrodes 23, 24. In addition, this configuration of the gap 25 makes it possible to adapt the reaction space 21 to accommodate different volumes, without having to change the outer dimensions of the reaction space 21 and thus of the entire container 20, which is particularly advantageous when the container 20 intended for automated processes. In order to adapt the reaction space 21 to different volumes, only the inclination angle of the side wall 28 has to be changed in the production.

FIG. 4 shows the underside of the container 20 according to the invention according to FIG. 3. Analogously to the container 1 according to the invention according to FIG. 1c), here too the first electrodes not visible here, ie for example electrodes which have the same polarity when an electrical DC voltage is applied, have two adjacent rows on a common contact surface 29. Thus, in this embodiment, 16 reaction spaces are always electrically coupled via their first electrodes. Overall, the container 20 thus has six common contact surfaces 29. The respective second electrodes 24 of each reaction space 21, which have the opposite polarity, for example when applying a DC voltage, are, however, uncoupled and each have their own contact surface 30. By this particular arrangement, the production of the container 20 according to the invention is simplified, while still a separate switching of each reaction space is possible. Overall, the electrical coupling of a plurality of first electrodes of a container reduces the complexity of the apparatus and, moreover, enables effective and reliable contacting of the electrodes from the underside, which will be illustrated below with reference to FIGS. 5 and 6.

In the embodiments described above, the electrodes 4, 5, 23, 24 are each formed semicircular. The electrodes can, however, for example, at least partially also plate-shaped, d. H. flat, be formed. In a preferred embodiment, z. B. the electrodes in the bottom region of the container in each case in a semicircular shape and further up in the course of the gap plate-shaped. However, other forms for the electrodes are conceivable.

FIG. 5 shows a schematic representation of the arrangement of contact elements 31 within a device according to the invention for contacting the containers according to the invention. The contact elements 31 are arranged on or within a device 32 designed especially for this purpose. The device 32 may be, for example, a plate or a grid. The contact elements 31 may be, for example, pin contacts, spring contacts or the like. In the present exemplary embodiment, the arrangement of the contact elements 31 on the device 32 is such that it is suitable in particular for electrically contacting the container 20 according to the invention according to FIGS. 3 and 4. The individual contact elements 33 shown here as black dots are provided for contacting the electrically coupled first electrodes or the common contact surfaces. The arranged in rows, shown here white contact elements 34, however, are for contacting the provided separately contacted second electrodes. In the present exemplary embodiment, therefore, a contact element 34 is provided for each uncoupled second electrode, while only one contact element 33 is provided in each case for the electrically coupled first electrodes. Thus, only one contact element 33 is required per double row of reaction spaces. All contact elements 33 may also be electrically coupled. As a result, the number of electrical connections can be significantly reduced, which reduces the manufacturing costs and the equipment required. Through the individual contact elements 34 assigned to each reaction space, the separate switchability of each reaction space is maintained.

FIG. 6 shows an alternative arrangement of the contact elements 31, which corresponds to that according to FIG. 5, with the exception that a total of three contact elements 33 are provided for the coupled electrodes. These three contact elements 33 are arranged in a row along the common contact surface of the coupled second electrodes. By providing two additional contact elements 33 for the coupled electrodes, the electrical contact can be improved and, moreover, the probability of poor or missing contact can be significantly reduced. In addition, this embodiment makes it possible to use two of the three contact elements 33 for a resistance measurement in order to check the presence of individual containers 15 within the frame 17 according to FIG.

The contact elements 31 are arranged on the device 32 according to FIGS. 5 and 6 such that, for example, the container 20 according to the invention as shown in FIGS. 3 and 4 must simply be placed with its underside on the device 32 in order to establish the electrical contact. The arrangement of the contact elements 31 corresponds exactly to the arrangement of the contact surfaces 29, 36 of the coupled first electrodes 23 and the uncoupled second electrodes 24th

FIG. 7 shows a perspective schematic representation of a device 35 according to the invention for contacting the containers according to the invention. The device 35 consists of a housing 36 in which a plate 37 is arranged, are mounted on the pin-shaped contact elements 38. The plate 37 corresponds to the device 32 according to FIGS. 5 and 6. The plate 37 with the contact elements 38 is vertically movable, the mechanism provided for moving the plate 37 not being depicted in detail in this illustration. The device 35 further comprises a table 39, which is horizontally movable, wherein also for the process of the table 39 provided mechanism is not shown in detail here. The table 39 can pass through the housing opening 40 into the interior 41 of the housing 36. The housing 36 thus represents a kind of garage, within which the electrical discharge can take place. This is advantageous for safety reasons, since work is done, for example, in electroporations with high-voltage pulses, which can pose a threat to the persons operating. The operator only needs to place the container with the reaction batches on the table 39, without any further contact with the device 35 according to the invention being necessary during the further method steps. If, for example, a container according to the invention, for example the container 20 according to FIGS. 3 and 4, is placed on the table 39, then the table 39 with the container is moved through the housing opening 40 into the interior 41 of the housing 36 of the device 35 according to the invention. This can be done automatically by means of a motor driven mechanism. If the table 39 with the container is completely in the interior 41, the plate 37 is moved with the contact elements 38 upwards. In this case, the pin-shaped contact elements 38 are passed through the corresponding holes 42 in the table 39, so that they can come into contact with the contact surfaces of the container. Thus, the electrical contact between the contact elements 38 and the electrodes of the container is made. Within the protective housing 36 then the voltage pulses for generating the electric fields in the individual reaction chambers of the container can be triggered.

The device 35 according to the invention is also particularly suitable for contacting the containers according to the invention within fully automated methods, in particular for methods with very high throughput numbers. In this case, a safe and reliable implementation of the method is ensured by the device 35 according to the invention. In deviation from the embodiment shown here, it would alternatively also be possible to leave the table with the container outside the housing and to move only the device with the contact elements vertically and / or horizontally to make contact with the electrodes. The electrical contact is likely to be made in this case only if the user has placed the container on the table and the device does not touch. Since in fully automatic process, the placement of the container is not done by hand, but by machine, this alternative embodiment would be quite advantageous, as a result, a more compact design of the device according to the invention would be possible.

FIG. 8 a) shows a schematic circuit diagram of an embodiment of an arrangement 45 according to the invention for carrying out the method according to the invention. The arrangement 45 has a pulse generator 46 which comprises two memory devices 47, 48. The memory devices 47, 48 are each capacitors that are charged to a predetermined electrical charge and can deliver defined voltage pulses by targeted discharge. The storage devices 47, 48 are charged to the predetermined charge by additional storage devices 49, 50, which are also capacitors, of an energy storage device 51. The memory devices 49, 50 are fed by a power supply 52 for this purpose. The interposition of additional memory devices 49, 50 between the power supply 52 and the memory devices 47, 48 has the advantage that the memory devices 47, 48 can be charged faster, whereby faster pulse sequences are possible. The memory devices 47, 48 are connected directly to power semiconductors, not shown here, via which the targeted discharge of the memory devices 47, 48 is switched. The Power semiconductors may for example consist of an IGBT or a MOSFET. However, other electronic components can be used by means of which the voltages and currents to be switched with the required switching times can be switched. The use of two memory devices 47, 48 enables the delivery of two short successive or merging voltage pulses, which may be advantageous in the electroporation of particular cell types. In these particular applications, a short high voltage pulse is followed by a longer, lower voltage voltage pulse, with both voltage pulses merging.

In the present exemplary embodiment, the pulse generator 46, that is to say both the memory device 47 and the memory device 48, is connected to a common electrode 56 via a measuring resistor 55. The common electrode 56 can be, for example, a plate electrode which is located in the bottom region of a container according to the invention and extends over all reaction chambers, in the present exemplary embodiment 96. In this exemplary embodiment, therefore, all the first electrodes of a container are electrically coupled, ie have the same polarity, for example when an electrical DC voltage is applied. The storage devices 47, 48 are further connected in each case via exclusively one reaction chamber associated switching elements 57 with the respective second electrodes 58 of the reaction space. The switching elements 57 are preferably relays. In the present exemplary embodiment, the second electrodes 58, which for example have a polarity opposite to the electrode 56 when a direct current voltage is applied, are individual pin-shaped electrodes which dip from above into the reaction space or the cell suspension or the reaction mixture. Since each second electrode 58 of one of the 96 reaction chambers is assigned a relay, each reaction chamber can be switched or controlled separately, so that the respective voltage pulse emitted by the pulse generator 46 exclusively leads to the generation of an electric field in the respectively connected reaction space. By the electrical coupling In this case, the expenditure on equipment, here in particular the wiring of the individual electrodes, can be significantly reduced in the case of the first electrodes as the common electrode 56. In the present exemplary embodiment, the 96 reaction spaces of the container can be switched separately via the 96 switching elements 57, so that the electrical parameters in each reaction space can be varied. The switching elements 57 are preferably connected sequentially, ie the generation of the electric fields in the individual reaction chambers takes place in succession. Alternatively, for example, two pulse generator could be provided, so that always two relays could be switched simultaneously, for example, to increase the overall operating speed. However, then the reaction chambers of the container would have to be practically divided into two areas, which would each be connected to a pulse generator, which would increase the overall equipment complexity.

The charging of the memory devices 49, 50 and the memory devices 47, 48 as well as the switching of the power semiconductors and the switching elements 57 is controlled by means of a control unit 59. The control unit 59 can be operated, for example, via a conventional computer 60. Moreover, in the present exemplary embodiment, the current during the delivery of the voltage pulse can advantageously be measured via the measuring resistor 55 and the control unit 61 so that control of the method based on the total charge output is made possible by integrating the currents in a specific time interval ( Q-control). In this case, the control unit 59 may cause, for example, that the respective relay 57 is opened as soon as a predetermined total charge amount is reached. The control of the method according to the invention by the control unit 59 will be described in more detail below with reference to FIG.

FIG. 8 b) shows a further embodiment of an arrangement 62 for carrying out the method according to the invention, which substantially corresponds to the arrangement 45 according to FIG. 8 a). The arrangement 62 distinguishes from the previously described arrangement 45 in that here no common first electrode is provided, but a total of six groups of first electrodes 63 are electrically coupled. The embodiment shown here is therefore particularly suitable for use with the container 20 according to the invention according to FIGS. 3 and 4 or the device 32 according to FIG. 5. The first electrodes 63 are each two rows of eight reaction spaces of a container, ie a total of 16 electrodes in each case electrically coupled, ie have a common contact surface. The pulse generator is therefore connected in this embodiment with respect to the coupled first electrodes 63 via the measuring resistor 55 with a total of six contact surfaces. The respective second electrodes 64 of each reaction space are in turn connected via switching elements 65 to the pulse generator. Since, in this embodiment, each second electrode 64 of a reaction space can be switched separately via a switching element 65 assigned to it alone, the generation of electric fields within each of the 96 reaction spaces can be separately controlled or the reaction space to be switched can be chosen freely.

FIG. 9 shows a flow chart illustrating the individual steps 70 to 84 of an embodiment of the method according to the invention. After the start of the routine, the programs for the voltage pulses are first detected in step 70. Thereafter, in step 71, a list of the pulse parameters for the selected reaction spaces is created. In step 72, then, the first or next switching element or according to the respective embodiment, the first and next switching elements, which enable a separate switching of the selected reaction space (s), is switched according to the list from step 71. In step 73, the electrical resistance of the selected reaction space is then first measured. In step 74, the measured resistance is compared with a setpoint. If the measured resistance is not within the target range, for example an empty reaction space, the routine goes back to step 72 and step 75 in step 75 Next switching elements or the next switching elements of the list are switched, ie the routine goes to the next selected reaction space, wherein the error routine is run again. If the resistance is within the target range, ie if the reaction space is filled with a correct cell suspension, then the routine proceeds to step 76. In step 76, the memory device or storage devices become the predetermined voltage U1 or the predetermined voltages U1 and U2 loaded. If a memory device is provided, then the method according to the invention is carried out with a voltage pulse with the voltage U1. If, on the other hand, two memory devices are present, then the method according to the invention can also be carried out with two voltage pulses having short-consecutive and / or merging into one another with the voltages U1 and U2. In step 77, the voltages for charging the memory devices are turned off and the power semiconductor for the first memory device (U1) is closed, so that the selected reaction space is exposed to the voltage pulse. The current flow can be measured and monitored via a measuring resistor. When using a memory device or a voltage pulse, the routine proceeds directly to step 79 or step 80. Alternatively, the power semiconductor of the first memory device (U1) may also be opened after a preset time, the routine then proceeding directly to step 84. On the other hand, if two memory devices are used to deliver two voltage pulses, the routine first proceeds to step 78. In step 78, after a preset time, the power semiconductor of the first memory device (U1) is opened while the power semiconductor of the second memory device (U2) is closed to output the second voltage pulse. In step 79, the charge is integrated based on the periodic current measurements and thus the respective total charge is determined. In step 80, it is first determined whether a preset maximum duration of the voltage pulse or the voltage pulses has been reached. If so, the voltage pulse is aborted through the error routine in step 82, ie, the routine proceeds to step 83. If the maximum pulse duration is not reached, then At step 81, it is determined whether the preset total charge has been reached. If not, the routine returns to step 79 and cycles through the cycle again. When the predetermined total charge is reached, the routine proceeds to step 83, in which the power semiconductor for the first memory device (U1) or possibly the second memory device (U2) is opened. In step 84 it is then determined whether the end of the list has been reached. If this is not the case, then the routine goes back to step 72 and goes through the entire cycle again. When the end of the list is reached, the routine is ended. The generation of the electric fields in each of the reaction spaces is thus switched separately, wherein the pulse parameters for each reaction space can be individually preset and controlled. The generation of the electric fields in the individual reaction spaces is carried out sequentially, wherein the order of the selected reaction spaces can be arbitrarily preset.

LIST OF REFERENCE NUMBERS

1

container

2

reaction chamber

3

wall area

4

first electrode

5

second electrode

6

gap

7

contact area

8th

contact area

9

contact area

10

line

11

line

12

bottom

13

floor area

15

container

16

fastening device

17

frame

20

container

21

reaction chamber

22

wall area

23

first electrode

24

second electrode

25

gap

26

surface

27

opening

28

Side wall

29

contact area

30

contact area

31

contact element

32

Facility

33

contact element

34

contact element

35

contraption

36

casing

37

plate

38

contact element

39

table

40

housing opening

41

inner space

42

holes

45

arrangement

46

pulse

47

memory device

48

memory device

49

memory device

50

memory device

51

Energy storage device

52

power adapter

55

measuring resistor

56

electrode

57

switching element

58

electrode

59

control unit

60

computer

61

control unit

62

arrangement

63

first electrode

64

second electrode

65

switching element

70 - 84

step

Claims (16)

1. A method for the electrical contacting of at least one container (1, 15, 20) provided with electrodes (4, 5, 23, 24), in which the electrodes (4, 5, 23, 24) of the container (1, 15, 20) are contacted by contact elements (31, 33, 34, 38), wherein the container (1, 15, 20) is first placed on a table (39) and the table (39) with the container (1, 15, 20) and/or the contact elements (31, 33, 34, 38) are moved vertically until the electrical contact is made between the contact elements (31, 33, 34, 38) and the electrodes (4, 5, 23, 24), characterised in that the contact elements (31, 33, 34, 38) are guided through at least one opening (42) in the table (39) from below for contacting the electrodes (4, 5, 23, 24).
2. The method according to Claim 1, characterised in that the contact elements (31, 33, 34, 38) are arranged on a device (32), preferably a plate (37) and the device (32) is moved vertically, in particular by means of a motor.
3. The method according to Claim 1 or 2, characterised in that the table (39) is moved by means of a motor for positioning the container (1, 15, 20).
4. The method according to any one of Claims 1 to 3, characterised in that an inner space (41) is provided in which the contact elements (38) are arranged.
5. The method according to any one of Claims 1 to 4, characterised in that a housing opening (40) is provided through which the container (1, 15, 20) and/or the table (39) is inserted in a housing (36).
6. The method according to Claim 5, characterised in that a voltage pulse for generating electrical fields in the container (1, 15, 20) is not triggered until the container (1, 15, 20) is located inside the housing (36).
7. A device (35) for the electrical contacting of at least one container (1, 15, 20) provided with electrodes (4, 5, 23, 24), with at least one table (39) for positioning the container (1, 15, 20) and with contact elements (31, 33, 34, 38) arranged on a device (32) for contacting the electrodes (4, 5, 23, 24) of the container (1, 15, 20), wherein the table (39) and/or the device (32) is/are vertically movable for establishing an electrical contact between the contact elements (31, 33, 34, 38) and the electrodes (4, 5, 23, 24), characterised in that the table (39) has at least one opening through which the contact elements (31, 33, 34, 38) can be guided from underneath for contacting the electrodes (4, 5, 23, 24).
8. The device according to Claim 7, characterised in that the device (32) is a plate (37) on which the contact elements (31, 33, 34, 38) are arranged.
9. The device according to Claim 7 or 8, characterised in that the device (32) can also be moved horizontally and/or by means of a motor.
10. The device according to any one of Claims 7 to 9, characterised in that the table (39) can also be moved horizontally and/or by means of a motor for positioning the container (1, 15, 20).
11. The device according to any one of Claims 7 to 10, characterised in that the table (39) is a perforated plate, wherein the number of holes (42) is preferably equal to the number of contact elements (31, 33, 34, 38).
12. The device according to any one of Claims 7 to 11, characterised in that an inner space (41) is provided in which the contact elements (38) are arranged.
13. The device according to any one of Claims 7 to 12, characterised in that a housing opening (40) is provided through which the container (1, 15, 20) and/or the table (39) can be inserted in the inner space (41).
14. The device according to any one of Claims 7 to 13, characterised in that it has at least one electrical storage device (47, 48, 49, 50) or can be connected to at least one electrical storage device (47, 48, 49, 50), wherein the storage device (47, 48, 49, 50) is preferably a capacitor.
15. The device according to any one of Claims 7 to 14, characterised in that at least one switching element (57, 65) is arranged between the storage device (47, 48, 49, 50) and the electrodes (4, 5, 23, 24) of the container (1, 15, 20), and/or in that an electrical switching element (57, 65) is assigned to each reaction space (2, 21) and/or each group of coupled electrodes (4, 23), wherein the switching element (57, 65) is preferably a relay.
16. The device according to Claim 15, characterised in that the switching elements (57, 65) are fitted directly to the contact elements (31, 33, 34, 38), preferably below the device (32) on which the contact elements (31, 33, 34, 38) are arranged.

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